CODE EXAMPLE FOR ELIXIR

elixir with syntax

def call(conn, _options) do
  with user_id when not is_nil(user_id) <- get_session(conn, :user_id),
       user when not is_nil(user) <- Repo.get(User, user_id)
  do
    assign(conn, :current_user, user)
  else
    _ ->
      conn
      |> Controller.put_flash(:error, "You have to sign in to access this page.")
      |> Controller.redirect(to: "/sign_in_links/new")
      |> halt
  end
end